A grammar is a classified collection of the rules or laws regulating the language Of which it professes to be an exposition. Every lan guage is subject to changes, either for the better or for the worse; and although in the case of a dead language a grammarian must consider and illustrate it mainly as it was at the time of its most perfect development, still he cannot avoid taking into considera tion the earlier and later forms of words and expressions, for in many instances the language in its perfect state cannot be fully explained without recourse being had to those forms of speech out of which it has arisen. Very great advantages may also be derived, especially in the etymological part, from a comparison of the language under consideration with its sister tongues, or with its mother tongue, where the existence of this is certain. But in a grammar for young people, such comparisons must be in a great measure useless; and all that can be done with advantage, is to apply to the language under consideration such principles as may have been established by comparative philology. As a grammarian has only to classify and explain the pheno mena or facts of the language which are generally known, he has little to add of his own; and that which principally distinguishes him from his predecessors is the arrangement of, and the manner in which he states and explains the facts. In this alone consist his merits or demerits.